Power transmission



May 5, 1959 H. w. GILFILLAN POWER TRANSMISSION Original Filed Jan. 19,1946 4 Sheets-Sheet 1 ,452 INI/EN TOR. HENRY W /LF/L. L/N

fram/5 V5.

May 5, 1959 H. W. GILFILLAN 2,885,578

POWER TRANSMISSION Original Filed Jan. 19, 1946 4 Sheets-Sheet 2 May 5,1959 H. W. GILFILLAN 2,885,578

POWER TRANSMISSION original Filed Jan. 19, 1946 4 Sheets-sneer s lao 2256 HENRY W G/LF/LL/Y l ATTORNEYS.

May 5, 1959 H. w. GILFILLAN 2,885,578

POWER TRANSMISSION Original Filed Jan. 19, 1946 4 Sheets-Sheet 4 IN V ENTOR.

,7770 FNK V9.

United States Patent-O POWER TRANSMISSION Henry W. Gilfiuan,

Corporation, Delaware Application August 23, 1951, 'Serial No. 243,276`now Patent No. 2,753,727, dated April 10, 1956, which is ya division ofapplication Serial No. 642,179, January 19, 1946, now Patent No.2,565,494, dated August 28, 1951. Divided and this application July 18,1955, Serial No. 522,639

11 Claims. (Cl. S10-96) Whittier, Calif., assignor to Chrysler -i1944,to me jointly with E. L. Bailey, there is disclosed a transmissionemploying an eddy current brake and clutch controlled planetary gearingahead of a manually operated change speed unit. In this arrangement thetorque multiplication for starting and acceleration of the vehicle isobtained by actuation of the eddy current brake 1 nec hanism, while forcruising drive of the vehicle the .eddy lcurrent clutch is operated.However, the arrange- 'rnent provides the same drive ratios forbreakaway and acceleration thus necessitating a compromise in driveratios between the ideal ratios for these driving conditions;individually. Moreover, the magnetic circuits disclosed .in that patentnecessitate in the sun gear rotor a lradially projecting toothstructure, non-magnetic spacers between the clutch and brake portions ofsaid rotor and a large overhanging portion, these features allcontributing to ,magnetic and dynamic unbalance in operation. Inaddition the patented mechanism includes a heavy magnetic fieldstructure and requires specially shaped tield coils.

It is the general .object of this invention to provide improvements inarrangement, construction and operation over the mechanism disclosed inmy prior patent.

Highland Park, Mich., a corporation of Thus, an object of my inventionis to provide an eddy ,current type transmission having distinct andideally -suited drive ratios for breakaway, accelerating, and cruisl ingdrives.

Another object is to provide an automotive eddy cur- -rent transmissionhaving the foregoing features and requiring no clutch pedal control forobtaining changes from one drive ratio to another.

A further object is to provide an automotive power i transmission havingan eddy current clutch and brake structure in advance of a suitablechange speed gearing, for instance, a planetary, unitary and amulti-forward speed and reverse countershaft unit in tandem, the eddycurrent structure and gearing being automatically controllable wherebymovement of the vehicle from rest is initiated with the eddy currentclutch in actuation control for instance, of the planetary gear set, andwith the countershaft type unit in underdrive and whereby cruising speedratio is obtained under driver control at predetermined vehicle speed byan upshift in drive ratio in the countershaft unit, and wherebyaccelerating ratio or kickthe control system disclosed in Figure 9;

value under cruising drive conditions, for example, even as low as 200r.p.m.

It is also an object to provide the driving member of the eddy currentclutch with concentric sets of opposite teeth, the anks of the teeth ofeach set converging toward the teeth of the opposite set.

A further object is to provide an eddy current structure having a sungear rotor of T-section and which may also have the portion of saidrotor in the magnetic circuit of the eddy current clutch devoid ofnon-magnetic spacers and radially projecting tooth structure.

Another object is to provide an eddy current transmission wherein theenclosing housing of the eddy current mechanism is made to form part ofthe magnetic circuits of one or both of the eddy current clutch and eddycurrent brake structures to thereby reduce magnetic flux leakage andeffecting a reduction in the mass of the overall mechanism.

Still another object is to provide in an eddy current transmission a sungear rotor having an annular iron portion in the magnetic circuit of theeddy current mechanism substantially free of magnetic unbalance andfacilitating the use of minimum air gaps between such rotor portions inthe magnetic circuit and the field coils of the eddy current mechanism.

A specific object is to provide an eddy current transmission having anovel cooling system for the magnetic structure whereby provision ismade for air cooling immediately adjacent the magnetic portion of thesun gear rotor.

It is also an object to provide an eddy current transmission in whichthe eddy current clutch and brake mechanism is separately housed fromthe transmission gearing and wherein the component parts of thetransmission gearing and eddy current mechanism may be readilydisassembled.

Another specilic objectis to provide a constant mesh synchronizedreverse drive and low speed drive employing oversize synchro blockerclutches to speed up the sun gear rotor when making manual shifts intoreverse drive and low gear.

Other objects and advantages of my invention will become more apparentfrom the following description taken in connection with the accompanyingdrawings wherein:

Figure 1 is a diagrammatic showing of the power plant and drivemechanism of a vehicle incorporating the present invention;

Figure 2 is a side elevational view of the power plant and transmission;

Figure 3 is a view taken in the direction of the arrows 3 3 of Figure 2showing the manual drive selector;

Figure 4 is a front elevation of a' detail of the manual selectorhousing showing the different selector positions;

Figure 5 is a longitudinal sectional elevation of the transmission of myinvention;

Figure 6 is a sectional detail of the eddy current clutch structuretaken at 6-6 of Figure 5;

Figure 7 is a sectional detail of the eddy current brake structure takenat 7-7 of Figure 5;

Figure 8 is a development of a portion of the driven member of the eddycurrent clutch;

Figure 9 is a diagrammatic view of the control mechanism and electricalsystem of the transmission;

Figure l0 is a longitudinal sectional elevation ofa modified form ofeddy current mechanism;

Figure ll is a diagrammatic view of a modification o Figure l2 is afurther control modication which may be employed in the control systemof Figures 9 and l1; and

Figure 13 is a modification of the arrangement in Figure 5 illustratingapplicants invention employing a multiplerdiscmagnetic devicein placeofthe eddy current brake for controlling the sun gear of the planetaryunit.

Referring now to the drawings wherein similar referrence characters Lareused to designate .corresponding parts of the structure, Figure lillustrates a typical arrangement of transmission mechanism in a vehicleembodying .the present invention. The vehicle engine A is coupled .tothe driving wheels 10 of the vehicle through `an eddy current powertransmitting mechanism B and change speed gearing C, .the .mechanism Bcomprising an electrically controlled eddy current clutch and brakestructure Vshown :indetail in .Figures 5, 6, 7 and a change speedgearing C comprising, as seen in Figures and 9, a planetary underdrivethe output of which drives a manually controlled .two-speed forward andreverse countershaft gearing hav- .ing automatically controlled directdrive ratio. As seen in .Figure l, the-output shaft 12 of the unit C isconnected .by means of the usual propeller shaft l14 with customary.dilerential gear `box 16 which in turndrives the axle -shafts 18.. .A1:3 axle ratio is preferred.

As best seen in Figure 5, the numeral 20 designates the zrear yend ofthe crankshaft of engine AA which drives the eddy current clutchmechanism generally designated by the letter D and which includes adrive member'22 `and a ydriven member 24. The drive member 22, whichalso yserves as the engine ywheel comprises an annular eleement 26 ofmagnetic iron lor other magnetic material, the periphery of which isformed as best seen in Figure 6, with a circumferential set of alternate.radially projecting teeth 28y and spaces 30 uniformly spacedcircumferentiallyirof Vthis member. The drive member 22 also has aforwardly extending hub 32 (Figure 5) secured by bolts .-34 to .the.crankshaft and portion 2,0 of the engine A. lhe'teeth28 of the4 drivemember constitutedenitepolar vprojections of the-.same polarity.

Thedrive member22furtherincludes a second annular element 36 also of.magnetic `iron or other Avsuitable magnetic material positionedconcentric to the element 2.6 "and also possessing a-circumferentialvset of uniformly spaced internal radially projecting teeth v38 whichteeth Vare separated as seen inFigure 6 by the spaces 40. As .alsoseenin FiguresS and .6, the two setsof teeth are separated by an annularspace for receiving a portion of `the driven ,member 24 .hereinafterreferred to. `More zover, the number of teeth in each setis the same andthe .teeth are preferably Yradially laligned both circumferential-.fly-and .longitudinally .of the axis of rotation of the drive member.yAs vin thecase of the teeth 28, theteeth 38.also constitute polarprojections of the same polarity, but are .nfopposite ,polarity to theteeth 23. The elements 26 and 36 carrying the teeth 28 and 38respectively, are .retainedLin .theaforesaid,relationship by anannularspider 42 Yofznon-magneticmaterial, for instance, stainless steel`iurbrass Ycarried byside projections 44.of vthe teeth 23 and secured tothese teeth by suitablefastening means, not fshown. The spider 42includes a .forwardly projecting shelf portion 46 non-rotatablysupporting the element 36 ofthe drivemember thus maintaining the teeth28 and 38 in the predetermined radially spaced relationship referred'toabove-and further including a shouldered flange portion 48 non-rotatablycarrying the familiar ring gear .50 .forming part of the engine startingmechanism.

Surrounding the drive and driven members of the eddy `current clutch isa housing formed of three annular stationary :casing elements orportions 52, 53, and 54 of lmagneticiron orsother magneticmaterialforming part of the eld structures of the leddycurrentmechanism. ,As :seen .in Figure 5, the :elements v52 and 54 aresecured as by bolts 55 to the engine `block ,56 andthe elements 52vand'53'are connected by an annular channel-like member 557oignon-magnetic.materialltted over annular shoulders of the housingelements respectively, and secured to the :housing elements ,as .by.bolts 58,.

4.. 62 which is-retainedA in position by a washer 64 and snap ring 66.The housing element 54 also includes a central bore 68 in which ispress-.iitted a bearing sleeve 69 of nickel iron composition, whichprovides a loose running lit with the hub 32 of the eddy current drivemember 22. The casing element 52 has an inner cylindrical surface 70concentric with the toothed ring 36 of the eddy current drive structureandseparated therefrom radially by an air gap in the order of ve to tenthousandths of an inch to provide operating clearance. As s een bythedouble-ended arrows 72 designating the magnetic circuit of the eddycurrent clutch the casing elements 52 and v54 form part of the magneticcircuit of the eddy current clutch D.

Rearwardly of the casing element 53 is a bore 74 in which is fitted anannular core or polepiece member 76 stationarily secured by bolts 77 tothe casing element 53. The member 76 carries an annular field coilassembly 7S, As indicated by the double-ended arrows S0 the casingelement 53 and the member 76 provide the -magnetic circuit for the eddycurrent brake structure E. Moreover, as best seen :in Figure 7 theperiphery of' the Vcore member 76 is provided with a circumferential setof alternate radially projecting external teeth 82 and spaces 84uniformly spaced `circumferentially of this member, and the casingelement 53 has a set of opposite internal radially projecting teeth 86concentrically arranged with and spaced radially of the teeth 82 Iand inradial alignment therewith, the teeth l86 being uniformly spacedcircumferentially of the casing 53 and separated by spaces S8. All theteeth 82 constitute polar projections of one `polarity and all the teeth86 polar projections vof similar polarity to each other but of oppositepolarity to that of ,the teeth 82.

The driven member 24 of the eddy current clutch D Yand which is also.the operating member of the eddy current'brake E comprises'an annularthinwalled dr m 90 of T-,section rotatably mounted b y its b ub 92onspaced Aneedle bearings 94 on a shaft 96 preferably of non-magneticmaterial, the latter being splined as at l98 to the drive member'22 ofthe eddy current clutch. The drum includes a relatively thin cylindricalshell 100 of magnetic iron or other suitable magnetic material-connected by a central web 102 to thehub 92, the web and *hub beingpreferably of non-magneticmaterial to'reduce flux leakage.

The 'forwardly ,extending portion 104 of the shell 100 of the drum 90 issolid throughout its cylindric section and arranged to rotate withslight clearance, ve toten thousandths of an'inch between the sets o fteeth 28,y and `V3 8 land concentric thereto, this portion of theydriven .memberr24 of the eddy current mechanism being rotatablerelative to-the polar projections'ZS and 38 of vthe 'drive member 22 andbeing cooperable therewith to perform the functions of the eddy currentclutch. The rearwardly extending portion106 of the shell v100 of thedrum 90 is similarly arranged between the setsof `teeth 32 and 86 of thestationary eddy current brake vield structure Ybut instead of beingsolid throughout, its cylindrical section iscut through at alternateplaces to provide a serrated edge of uniformly spaced alternate teeth107 and spaces 108 (see Figure 8.) extending axially of the drum andsubstantially the axial length. of the teeth 82 and 86. The teeth 107are of equal .number to the teeth 82 and 86 and coextensivecircumferentially therewith so 'that the teeth .82, ,86, and 107 areadapted to be radially aligned in `operation for reasons 'hereinafterstated. Preferably .the teeth107 will'be of rectangular form andcomplementaryin shape to spaces 108.

The T-section of the drum 90 has the advantage of-reducing overhang ofthe portions 104`and 106thereofthus reducing distortion in operatingYthe eddy current brake ,end clutchand'likewise facilitatesthe useofjsmaller `-air igapsbetween the v,drum and its respective'eldstructures. Moreoven the freedom 'from radially projecting 4teeth Senables a reduction in the mass ofthe drum to a minimum yto therebyminimize its inertia.

The hub 92 of the driven eddy current member 24 ex'- tends rearwardlythrough a supporting ball bearing 109 carried in the brake pole piece 76and is provided with gear teeth or splines 110 constituting the sunvgear of a planetary gearing F. The ball bearing 109 is retained in themember 76 by a snap ring 112 and serves to locate the member 24 throughthe shoulder 114 of the hub 92 and a snap ring 116 thereon. The eddycurrent drive member shaft 96 has an oil seal 118 between it and themember 24 and a further oil seal is provided by a forward projecting hub120 of the brake pole piece 76 which is provided with oil grooves 122adjacent the hub 92. These oil retainer structures facilitatecontinement of oil of the transmission gearing in the housing 124, 125enclosing such mechanism. It will be observed that the shaft 96 has anend flange 126 located between the crankshaft portion 20 and eddycurrent drive element 22 to locate this shaft axially.

The shaft 96 is drivingly connected to the annulus 12S of the planetaryunit F through a splined connection 130, the annulus being retained onthe shaft by a snap ring 132. The spider 134 of the planetary gear setcarries the planet pinions 135 and is the output member of the planetarygear set and further drivingly connects the input shaft 136 of thecountershaft unit G through an element 138 having a splined connectionat 140 with the spider 134 and a splined connection at 142 with theshaft 136. A snap ring 137 retains the element 138 in axial position onthe spider.

In operation of the mechanism so far described, rotation of the enginecrankshaft 20 in the usual clockwise direction looking rearwardly of thetransmission will cause corresponding rotation of the eddy currentclutch drive member 22. If the eld coils 62 and 78 of the eddy currentmechanism are open-circuited, that is, deenergized, the reaction of theshaft 136 (which is assumed to be drivingly connected to the vehicledrive wheels) on the planetary spider 134 will cause the annulus todrive the su-n gear in reverse direction at approximately 21/2 times the'crankshaft speed, no torque being then transmitted to the countershaftinput shaft 136.

If now the field coil 62 of the eddy current clutch mechanism beenergized, magnetic flux will flow in the iron portions 54, 52, 36, 32,and the portion 69 and across the air gaps between the adjacentrelatively movable members or elements of the eddy current clutchstructure. The direction of flow of the magnetic lines of force willdepend upon the direction of current flow in the field winding 62, butwhether the same be in one direction or the other the result upon theeddy current clutch mechanism will be the same and hence the arrows 72in Figure 5 have been shown double-ended. Upon creation of the magneticfield it will be noted from Figure 6 that points of high ilux densitywill exist where the flux path through the portion 104 of the drum 90 ofthe driven member is between the polar projections or teeth 28 and 38and that points of low density will occur where the flux path throughthe portion 104 is across the opposite bases of the spaces 30 and. 40between the teeth 28 and 38 respectively. Hence, as each point on theportion 104 of the drum 90 passes through points of high and low fluxdensity and so long as relative rotation exists between the teeth 28, 38of the member 22 and the portion 104 of the drum 90, and there is ow ofmagnetic llux generated by the eld coil 62, eddy currents will beinduced in the portion 104 of the driven member, that is the memberopposite the teeth, having a direction of ow perpendicular to the flowof the main uX and in accordance with Lenzs law creating a magnetic fluxopposing the main flux and tending to oppose relative rotation betweenthe drive and driven members of the eddy current clutch structure thusinducing adriving torque in the output member 24 which is a maximum whenthe path represented by the arrow 72 in Figure 5 through the 6 eddycurrents are' maximum, that is, at maximum slip of the member 24. As theengine speed approaches that of the shaft 136 through balance of powerinput and load, the member 24 will tend to approach the speed of thedriving member 22 and to rotate at synchronism therewith and when thisoccurs a matter of seconds after energization of the field coil 62, theplanetary gear set F will be substantially locked up as a unit and drivewill then be transferred from the engine to the shaft 136 at a 1:1ratio. It is to be noted in this connection that the engine drives theannulus 128 at 1:1 and the member 22 and the sun gear 110 receive theirdrive from the member 24. In actual practice there always will bepresent some slip depending upon torque such being minimized at cruisingspeeds of the vehicle. Hence the actual drive ratio will be somewhatunder 1:1 on starting drive through the eddy current clutch and will besubstantially 1:1 at cruising speeds of the vehicle. It is also to benoted that because of the toothless construction of the portion 104 ofthe drum 90 the magnetic flux across the teeth 28, 38 at each point inthe portion 104 is substantially the same. This makes it possible tominimize magnetic reluctance between teeth 28 and 38 and provides asmoother control of the clutch mechanism.

lf the eld coil 62 of the eddy current clutch be deenergized and the eldcoil 78 of the eddy current brake mechanism energized, magnetic fluxwill flow in an endless path denominated by the arrows 80 in Figure 5through the casing 53, core member 76 and portion 106 of the drivenmember 24 crossing the air gaps between the portion 106 and the casingand core members respectively. As illustrated in Figures 7 and 8 theportion 106 of the drum has axially projecting teeth formed thereon.These teeth define polar projections that are spaced circumferentiallyof the drum 90 from one another in such manner that they may alignradially with the teeth 82 and VS6 of the field members 53 and 76 andwith the spaces 84 4and 88 between these teeth in alternate fashionduring rotation of the driven member 24. When the teeth 82, 107, and 86are all in radial alignment, the flux owing in the field elements 53 and76 and teeth 82 and 86 will flow through the teeth 107 and thus willencounter relatively low resistance to flow, the reluctance of the vairgap between positively disposed teeth 82 and 86 having been reduced bythe iron in the teeth 107. Correspondingly, when the teeth 107 areradially aligned with the spaces between the teeth 82 and the spacesbetween the teeth 86, the flux will encounter relatively greatresistance to flow because of the reluctance of the large air gap thenbetween the teeth 82 and 86. Thus, the flux is at a maximum when teeth82, 107 and 86 are aligned and at a minimum when teeth 107 are out ofalignment with teeth 82 and 86. I i

Accordingly, during rotation of the member 24 the flux will liuctuatebetween maximum and minimum values, the frequency thereof beingdetermined by the speed of rotation of the member 24 and in consequenceof this relative rotation eddy currents will be induced in teeth 107 andin the teeth 82 and 86 flowing in a direction perpendicular to the flowof the main ux and in accordance with Lenzs law induce a magnetic fluxof their own which will react with the main llux and oppose relativemotion between the rotor 24 and field members 76 and 53. lnasmuch as themember 24 will at this time be rotated counterclockwise, that is,opposite to the crankshaft 20, the effect of the eddy current flux willbe to slow down the reverse rotation of the member 24 and bring the'same'to a stop whereupon the direct magnetic pull across the polarprojections 82, 107, and 86 will thereafter hold this member stationaryand the planetary gearset F will through reaction on the sun gear 116 ofmember 24 transmit a torque multiplying drive to the countershaft unitshaft -136 which will be accelerated in underdrive "ratio at a speeddependent upon engine speed. It will be appreciated that torque will beimposed on shaft 136 from the instant that member 24 begin ste slowdownand therefore, the torque application will be smooth and gradual, theeddy current brake serving asa smooth acting clutch. Acceleration lofthe vehicle with the planetary in 'underdrive may be `continued as longas desired and when changeover 't0 vthe eddy ,current clutch is to beeffected, the coil 7S will be deenergizedv and, coil 62 cuergizedwhereupon the eddy current brake E will `be released .arld eddy currentclutch D will magnetically .couple themember 24 to the driving member 22for forward rotation therewith.

It is to be observed that the Yteeth 2S of the eddy current clutchmember 22 have substantially parallel sides for a considerableportion oftheir length. The purpose of this is to eliminate the use of excess ironfor carrying the necessary magnetic flux. The member is designed tostart the tooth structure from a base circle providing vsufficientironarea and to maintain this area constant by paralleling the sides of theteeth to a point adjacent the tips of the teeth at which place thesidesof the teeth are tapered convergingly to produce saturation of 'the ironat this point. lt will be observed that the teeth 38, 82, and Se arelikewise tapered for the same reasons.

During operation of the eddy current brake E there is a considerableamount of heat generated and to provide a means of air circulation, theannular casing member 57 .and the casing element 52 are provided withopenings 144 and 146 respectively; the spider 42 ,of drive member 22with openings 1d?, and driven member 24 with openings 150. All theseopenings; are arranged circumferentially in suitable number around theirrespective members. In addition the element 36 of the drive member ,22`iS provided with vanes 152 spaced at the circumference of that element,The teeth 2d and 33 and -vanes 152 will serve as air impellers, andsince the `Irlember 22 always rotates at engine speed, continuouscirculation of air will be provided so long as the engineis operating,the air entering at 146 and moving in the direction of the arrows 154and out the openings 144. It will be `understood thatl suitablel screensmay be provided for the openings 144 and 1,456,

Referring now to the countershaft change speed gearvset G, it will beseen from Figure that the shaft136 extends rearwardly through the ballbearing 156 retained in a bracket S by snap rings 16h. The bracket 158`issecured to the housing 124 by suitable means not shown. Shaft13o-terminates in a cone-shaped clutch portion 162 and a hollow portion164 thereofV provides space for a roller bearing 166 which pilots theforward end 1,67 of the tail shaft 12, the opposite end of the tailshaft being supported by and extending through a ball bearing 168retainediu a removable housing 1659 by retainer 170.

Integral with the shaft 136 is a pinion 171` which is in constant meshwith a gear 172. The latter is rotatable on roller bearing 173 andrdrives a countershaft 174 through an overrunning clutch H ofconventional type such that when the shaft 136 drives in the usualclockwise direction (looking from front to rear) then clutch H willengage to lock the gear 172 to countershaft 174 whenever the gear 172tends to drive faster than the countershaft, but whenever the gear 172tends to rotate slower than the countershaft 174 then clutch H willrelease whereby the shaft 136 under certain conditions may readily dropits speed while the countershaft 17 4 continues to revolve.

.Countershaft 174 is rotatably supported on roller bearings176 carriedby a rod 17S held in the housing 124, and comprises cluster gearsv 180,1.82 which-respectively provide drive in underdrive and reverse in thecountershaft gearing. Freely rotatable on the shaft 12 through rollerbearings 183 is the underdrive gear 184 which is in constant mesh withcountershaft gear 180. Reverse gear 18.6 vis also free on shaft 12 andconstantly meshes with idler gear 1.88 which in turn is in constant meshwith the countershaft reverse gear 182. Hence, all gearing for- Ward andreverse is' in constant mesh and there isfno' shifting of mytransmission. A hub 19o is splined on shaft 12 and carriesy therewith amanually shiftable sleeve 192 having clutch teeth 194 which sleeve isadapted to shift from the Figure 5 neutral position either forwardly toclutch with clutch teeth 196 of gear 134 or else rearwardly to clutchwith clutch teeth 198 of gear 136. It will be observed that suitableblocker synchromesh mechanism 260 is provided to facilitate smooth andnoiseless engagement of the sleeve 192 with the teeth 196 or 19E.inasmuch ,as any suitable type of blocker synchromesh mechanism may beused, this part of the mechanism is not described in detail, it beingdeemed sufficient to briefly refer to salient parts thereof.

lt will be noted that the synchro blocker clutches for forward andreverse drive of the constant mesh gearing are each oversized, that ismuch larger than conventionally used. This is desirable to facilitatesmooth engagement of the clutches while overcoming the substantialinertia effect of the sun gear carrying or driven member 24 whichrotates backward under urging of the engine and about 21/2 times engineidle speed when the coils 62 and 78 are both deenergized.

Sleeve 192 is operably connected to a shift rail of conventional form,not shown, which is operable through the selector lever Ztl?. seen inFigures 3 and 9 forming part o f the steering column mechanism 264. Thelever 2412 connects as by a suitable spline with a tubular shaft 296shown in phantom in Figure 2, having at its lower end a lever 2h13connected through link 21h, bell crank 212, and link 214 with a lever216 which in turn operates a lever not shown, within the transmissionhousing connected to the shift rail that operates the sleeve 192. Asseen. in Figure 4, the shift lever 202 operates in a zigzag slot 218 ofthe steering column housing and is so shaped to prevent movement of theselector lever directly from for.- ward drive position to reverse driveposition or vice versav in the same vplanar motion while the vehicle isoperating in one of these drive conditions. in this connection thesplined coupling of the selector lever with the shaft 206 is arranged topermit sufficient rocking movement of the lever to accommodate operationof the selector lever from one horizontal portion of the zigzag slot tothe other.

Slidably splined as at 219 is the automatic clutching sleeve I which,under certain conditions, is adapted to shift forwardly through blockersynchromesh mechanism 220 to clutch with teeth 222 carried by the pinion171 thereby positively clutching gear 184 directly with the shaft 136.This sleeve l is adapted to step up the speed ratio in the countershaftgearing from free-wheeling indirect drive to twofway direct drive whenthe manual selector sleeve 192 is in forward drive position, and to stepup the speed ratio in reverse. rive by driving the counter'- shaftcluster through the gear 18d-180, thus providing a two-way reverse drivethrough the countershaft gearing including the sleeves 192 and I thefree Wheel clutch H overrunning. The blocker mechanism is adapted tolimit engagement of the sleeve l with the clutch teeth 222. Thus whenthe relative speeds of these elements are asynchronous the teeth of theblocker mechanism in this control operation will lie in the path of theforward shift of sleeve l and when their relative speeds areapproximately synchronous the teeth of the blocker will permit the teethof the sleeve J to pass between them to allow clutching to takeplace.

Forinstance, when driving in indirect forward drive in the countershaftgearing above a predetermined vehicle speed, direct drive therein isobtained by the driver letting up on the usual accelerator pedal 224thereby allowing spring 226 to perform a closing movement on the enginethrottle valve 223 and cause the engine to rapidiy coast down. When thisoccurs the engine along with the shaft 136, pinion171, gear 172 all slowdown, while shaftlZ along with gear 134 continues their speeds byaccomgears required in the change speed gearing of lInodation offreewheeling unit Hl which now overruns; The engine slows down untilteeth 222 are brought to approximate synchronism with sleeve J whichthereupon automatically shifts to clutch with teeth 222 resulting in atwo-way direct drive from pinion 171, through sleeve J to gear 184thence through sleeve 192, hub 190 to shaft 12, the clutch Hoverrunning. When driving in indirect reverse drive a stepup maysimilarly be obtained but the drive then will be indirect from gear 171through sleeve J to gear 134 and gear 180.

The transmission is also provided with suitable control means includingmotor means, for controlling power shift of sleeve J. Referringparticularly to Figures 2 and 9, ythere is illustrated a pressure uidoperated motor K utilizing air pressure for its operation. Forconvenience, this motor is arranged to operate by the vacuum in theintake manifold system of the engine under control of electromagneticmeans illustrated in the form of a sole- A'noid L. The term vacuum iscommonly used to denote pressures less than atmospheric and it is inthis sense that I use this term and not in the strict sense of Zeropressure or absolute vacuum.

Forward shift of the sleeve I is effected, under control of the motor Kby reason of a spring 230 having its upper 'end hooked over a shaft 232carried in the housing 124 of the transmission C. A shift yoke 234 ismounted to freely rock on the shaft 232 and engages the shift groove 236of the sleeve I, the yoke having a plurality of arms, one of which isprovided with aforwardly extending portion 238 carrying a lateral pin240 which engages the yoke portion 242 of an upstanding lever 246. Thelever 246 'is fixed to a rockshaft 248, which also has fixed thereto abellcrank follower lever member having lever arms 250 and 252. The endof lever 252 is connected to the lower end of spring 230 and lever 250carries an adjustable abutment 254 for adjusting the lost motionrelationship between the lever 250 and a reciprocatory rod 256 of themotor K as will presently be apparent.

Spring 230 acts to yieldingly urge engagement of the sleeve J, actingthrough the lever 252, shaft 248 and lever 246, to cause the pin 240 toswing the yoke 234 forwardly on its shaft 232 until, when the sleeve Jis fully engaged, a stop pin 258 engages the forward portion 260 of theyoke portion 238. This limits the rearward swing of the lever 250.

Arranged for engaging the abutment 254 during its arcuate movement aboutthe axis of the shaft 248 is a thrust-imparting leader member in theform of the reciprocatory rod 256 aforementioned having an enlargedcentral portion 262 slidably supported in the bore 264 of the motor K.

Motor K comprises a cylinder 266 which contains a piston 26S, hereinillustrated as of the diaphragm type. This piston has its outer portionsecured to the cylinder 266 and its central portion xed to the rod 256,the piston and rod being urged forwardly in a direction to release thesleeve J by a spring 270 which is much stronger than the spring 230. Asuitable type of releasable holding means is provided for the rod 256 soas to releasably hold this rod and the piston 268 rearwardly retractedagainst the action of the spring 270 and independently of thecontinuance of vacuum until it is desired to urge disengagement of thesleeve J. This releasable holding means is illustrated in the form of alatch 272 which, underthe action of a rat trap spring 274 catches on therearward shoulder of a detent 276 in rod portion 262. At this time theleader rod 256 moves rearwardly further than the follower lever 250 byan amount represented by the gap 278 between the abutment 254 and lefthand end of the rod 256 such that on releasing the latch 272 the f od256 may move forwardly the amount of this gap without requiring thesleeve J to move from its engaged position toward its disengagedposition.

The vacuum supplied to the working chamber 280 is under control of theaforementioned solenoid L which comprises an armature plunger 282 havingvalving ports 284 and 286. In Figure 9 the solenoid L is energizedthereby raising the plunger 282 against the spring 288 to seat the valve286 and shut olf the vacuum supply to chamber 280 and at the same timeunseat valve 284 so as to vent this chamber through the passage 290,chamber 292 and vent passage 294. When the solenoid is deenergized, thenspring 288 lowers the plunger 282 thereby seating the valve 284 to shutotf vent 294 and open valve 286 thereby opening the chamber 280 to theengine intake manifold 296 through passage 290, chamber 292, chamber 298and pipe 300.

A certain lost motion is provided between plunger 282 and the inwardlybent linger 302 of latch 272 so that when the plunger moves downwardly,the latch may subsequently catch detent 276 when vacuum operates thepiston 268, the parts then remaining in the shifted positionindependently of vacuum in the chamber 280 until the solenoid L isenergized to release the latch and vent the chamber 298.

It is deemed preferable to provide a speed control for the energizationof solenoid L so as to insure automatic release of the sleeve J below apredetermined car speed and to accommodate automatic engagement of thesleeve J above a predetermined car speed. Whenever the vehicle is inforward speed range driving condition the manual sleeve 192 is shiftedforwardly to the forward drive position so that by driving a governorfrom the countershaft 174, it is possible to provide a speed controloperation proportionate to the speed of travel of the car when driven bythe engine. Driven from the countershaft gear 304 is a suitable governorM, Figure 9, of any suitable type, this governor operating a sleeve 305outwardly along its drive shaft 308 as the car speed increases.

It is preferred that the governor should call for a stepup in'driveratio by operation of the sleeve J at a predetermined car speed andshould maintain this condition during engine retardation suicient tosynchronize the speeds of teeth 222 and sleeve J. To accommodate thisaction the governor is so constructed as to call for a downshift at acar speed somewhat under the speed at which step-upy is called for. Inorder to facilitate step-down from engaged position of the sleeve J whenbringing the car to a stop or when greater acceleration is desired Ipreferably provide means for unloading the drive torque on the teeth ofthe sleeve J. This relief means is arranged to function automatically inresponse to forward travel of rod 256 from a position corresponding tothe engaged position of the sleeve J to a position corresponding to thedisengaged position thereof (shown in phantom in Figure 9). Preferablythe relief means is in the form of a system of grounding the primarycoil terminal 310 of the usual distributor 312 of the engine ignitionsystem whereby the engine ignition may be momentarily renderedinoperative thereby unloading the torque at sleeve J to insure itsrelease by spring 270.

The ignition interruption is under control of an interrupter switch Owhich is closed to ground the ignition by a bridge piece 314 upon upwardmovement of the ball 316, the latter transferring its movement to theplunger 318, spring 319, cup 320 to cause the bridge piece 314 to closethe switch and electrically connect the terminals of switch O. The body322 of the switch O has an inturned seat at its lower end to prevent theball 316 from falling out. A spring 324 urges the switch to openposition.

When the rod 256 is moved to the right in Figure 9 upon admission ofvacuum to motor K to condition the sleeve J for upshift, the portion 326on rod 256 moves the ball 316 upwardly to close the switch O. The switchagain opens when the recess 328 on rod 256 is aligned with the ball 316.During downshift operation by the spring 270 a similar but reversemovement of the rod 256 takes place, the switch O being operated duringmovement- 11 of the rod 256 in taking up the gap 278 Figure 9 andgrounding the ignition in the interval of time between operation oftherod 256 between portions 328 and 326 respectively. i

Referring now especially to Figure 9 for the electrical system of thetransmission and various control instrumentalities including thosedescribed above and which illustrate the various instrumentalities intheir positions with the vehicle at rest, and engine ignition on, thedriver operated ignition switch 329 comprising the conductor 330 shownin on or closed position, electrically connects contacts 331 and 332.Contact 331 extends by conductor 333 to battery 144 and thence to ground334 by conductor 335. Contact 332 extends by conductor 336 and branchconductor 337 to the engine ignition system herein shown in part ascomprising coil 33S, distributor 312 having the primary terminal 310 andgenerator 339 shunting the battery 144.

The. conductor 336 extends to a 4-pole switch 340 operated by governorM. The switch 340 is provided with terminals 341 and 342 adapted to bebridged by a conductor element 343, the latter being carried by the link306 of the governor. A conductor 334 extends from the terminal 342 tothe solenoid L and from there by conductor 345 to terminal 341A ofswitch 340 and thence to ground 346 through a conductor 343A alsocarried by the link 306. The switch 340 has a further terminal 342Awhich is adapted to be connected in circuit with the terminal 341A bythe conductor 343A which bridges the same when the switch 340 is inclosed position as shown. In. the circuit as shown the solenoid L isenergized, the motor K vented and sleeve I in its neutral or disengagedposition.

' A second conductor 347 branches from the conductor 336 to a terminal34S of a switch generally designated by the. numeral 349 operated by themanual gear selector 262. The switch 349 has a movable conductor bar 350which is adaptedv to bridge the terminal 348 and a second terminal I351to close this switch. The conductor bar 35) is carried on a rod 352 anda spring 353 acting between the insulated switch housing 354 and the bar350 urges the switch to closed position. The switch is actuated by a cam355 under control of the manual selector 202. As shown, the selector isin neutral position with the switch open. Movement of the selector toforward drive position or reverse position brings the low portion 356 ofcam 355 opposite the rod 352 allowing the switch 349 to close.

A conductor 357 extends from the terminal 351 to the movable switch arm358 of a rheostat switch 359 having a variable resistance 360automatically controlled by a governor N operably connected to theswitch arm 35S. One end of the resistance is connected to a terminal 361and the other end to a terminal 362 with taps taken oft at intermediatepoints and directed to intermediate terminals. When the switch arm 358is in contact with the terminal 361 maximum resistance will be in thecircuit and when the arm is in contact with terminal 362 there will beno resistance in the circuit.

A conductor 363 extends from the terminal 362 to a kickdown switchcomprising the two position double pole snap switch 364. The switch hastwo sets of terminals 365, 366 and 367, 368 between which a snap actionbar conductor 369 having an operating finger 376 may function. Theconductor 363 connects with the terminals 366, 367, that is one terminalof each set. A conductor 371 extends from the terminal 365 to the eddycurrent clutch coil 62 and the latter connects with ground 372. Terminal36S is connected byconductor 373 to the eddy current brake coil 7S andthe latter connects with ground 374.

The switch 364 is shown in its normal position closing thecircuit tocoil 62. In connection with current ow to this coil it will be notedvthat. the governor N is intended to be driven by the engine A, forexample, by the generator drive shaft, and functions to open the circuitbetween conductors 357 and 363 gradually when the, vehicle 12 contesto astop and. to gradually'energize. the coil l62 by cutting out resistancewhen the vehicle is started from rest.

The switch 364 is operated to close the circuit to coil 78., bydepression of the accelerator pedal 224 acting through a link 376,connected to the arm 37S of a bellcrank 380 pivoted at 382. A link 384connects the bellcrank with the throttle valve 228 through a lost motionconnection 386 (see Figure 2), which permits overtravel of theaccelerator pedal. The other arm of the bellcrank has two spacedoperating fingers 38S and 390 respectively for engagement with theswitch operating arm 370. Upon depression of the accelerator pedal whichis illustrated in its released position in Figure 9, the finger 33Stakes up the space between it and the switch control arm 370 andactuates the latter to open the circuit to coil 62 and close that to 73.if desired, the spacing between fingers 388 and 39.0 may be suicientthat the throttle is operated to wide open position by full depressionof the accelerator before the switch 364 is actuated, thisbeingfacilitated by the lost motion connection 386 (Figure 2) the throttlearm. 391 being then against the stop 392. It will be observed that thelost motion permitted in operating the switch 364 is also operable inreleasing movement of the accelerator so that the switch is not operatedto re-energize the coil 62 until the accelerator is practically fullyreleased. This lost motion makes it possible to operate the throttleWithin a considerable range without obtaining kickdown or once havingobtained the latter it enables continuous operation in kickdowncondition of the transmission without the necessity of maintaining fullthrottle opening. The spring 226 returns the accelerator upon releasethereof andy returns the switch 364 to normal position.

rlhe. ignition interruption circuit under control .of the switch Oconnects with the ground 346 through governor switch 340 when the latteris closed, terminal 394 of switch O connecting with terminal 342A ofswitch 340 through conductor 393. The other terminal 396 is connected tothe terminal 3l@ of the distributor by a conductor 393.

Operation In describing the operation of the transmission, let it oeassumed that the vehicle is at rest with the ignition switch 329 closed,the engine A idling and the gear selector lever 202 in neutral. Sincethe governor switch 340 is also then closed the solenoid L circuit isenergized and the core 282 will be in the position shown in Figure 9with the valve 284 open and motor .K vented, thus maintaining sleeve Jin disengaged position. It will be understood that during the time theignition switch 329 is open the solenoid L is deenergized opening thevalvev 286. However, since the engine is dead there is no vacuumavailable and the motor remains in vented position under urging of thespring 273 which is the disengaged. position of the sleeve J in whichposition the sleeve was actuated when the vehicle was last brought torest. The aforesaid conditioning occurs immediately that the ignitionswitch is closed and thereby prevents the sleeve I from being con.-ditioned for engagement while the car is at rest.

In order to start the vehicle for forward movement, the gear selectorlever 202 is swung clockwise about the axis of the steering column toforward drive position thus causing operation of link 210, bellcrank212, link 214, and lever 216 to shift the sleeve 192 forwardly of Figure5 to thereby mesh the teeth thereof with the clutch teeth 196 of lowspeed gear .184. Engagement willbe facilitated by the fact that. thesynchro clutch is oversize. At the. same time the accompanying movementof cam plate 355 will permit the selector switch 349, plunger 352 tomove forward under urging of spring 353 and enable conductor bar 350 tobridge the terminals 348, 351 to close this switch. Since the rheostatswitch 359 is preferably open circuited at this time no current will.flow to either coil 62 or 7S. and engagement of the clutch sleeve 192 isassured without clash of the teeth. It is preferred,

especially if the rheostat switch be omitted, that the cain plate 155 bedesigned such that the switch 349 will remain open until the plate 355has been swung sufficiently to fully engage the sleeve 19'). with theclutch teeth 196. A similar arrangement is desired when engaging thesleeve 192 in reverse. This likewise will prevent clash of the teeth inshifting the sleeve 192.

Hence, with the arrangement in Figure 9, shift of the sleeve 192 intoforward drive position does not immediately energize the eddy currentclutch coil 62 such occurring when the engine driven governor N hasclosed the rheostat switch 359 by causing the control lever to contactthe terminal 361. This will occur upon slight depression of theaccelerator to speed up the engine and the governor N driven thereby. Itshould be noted in this connection that at engine idle speeds therheostat switch is open and thus no creep torque whatever may betransmitted to the tail shaft 12 at this time. Once the switch 359 isclosed current will flow to the coil 62 from the battery 144 throughconductor 336, 347, switch 349, conductor 357, rheostat 359, conductor363, switch 364 (the terminals 365, 366 of the latter being bridged),conductor 371, and thence to ground 372 returning to battery by ground334. Moreover, as the engine speed is increased the rheostat arm 358will be moved under control of governor N to reduce the resistance inthe circuit, thus obtaining gradual increased energization of the coil62 to effect a smooth start of the vehicle by gradually reducing theslip between the dri er 22 and runner 24 of the eddy current clutch D.Depression of the accelerator pedal 224 will therefore cause the vehicleto be smoothly accelerated in a forward direction with the eddy currentclutch operating the planetary gearing F in fastest speed ratio, heredirect drive, two elements of the planetary, to wit, the sun gear andannulus being driven in substantially 1:1 ratio, by the runner 24 andcrankshaft 20 respectively. In this connection it should be observed asexplained above that in starting the vehicle from rest with the clutchcoil 62 energized, the planetary is conditioned for operation in `1:1ratio but the actual ratio is greater than this by reason of slip of therunner 24. This slip is automatically reduced as rapidly as theresistance 360 in the coil circuit is cut out and when the latter occursthe planetary is for all practical purposes established in 1:1 ratio.The output of the planetary comprising the spider 134 drives the inputpinion 171 of the countershaft gearing and since the sleeve J is at thistime disengaged the drive is indirect or underdrve from the pinion 171to gear 172, freewheel clutch H, pinion 180, gear 184, clutch teeth 196,clutch sleeve 192, hub 190 to shaft 12. This is overall second speedratio freewheel drive, i.e., breakaway speed ratio drive (that is,normal starting speed ratio drive) of the transmission and providessubstantially a 2.5:1 ratio. With a 3 to 1 axle ratio this provides anoverall 7.5 :1 ratio.

When the vehicle has been accelerated of approximately miles per hourthe governor M switch 340 will open thus deenergizing the solenoid L andoperating the valve mechanism to admit vacuum to the motor K to causethe diaphragm 268 to compress the spring 270 and shift the rod 256 tothe right in Figure 9 to the position shown in phantom whereupon thelatch 272 which was released by deenergization of the solenoid L willseat in the groove 276 to prevent return of the rod should the vacuumforsome reason or other thereafter especially at wide open throttle be re.duced below the effective strength of spring 270. Simulf taneously thespring 230 will act to move the abument 254 forward to take up the gapcreated between it and the left end of rod 256 and will also actuate thesleeve J yoke to shift the sleeve J to drive block position with theends of the teeth of the sleeve J .abutting the teeth of blocker 220.Upon `subsequent release of the accelerator pedal 224 to allow theengine to coast sufficiently to a vehicle speed the blocker 220 and todropV the speed of clutch teeth '220' toapproxirnafe synchronism withthe sleeve J the latter will pass through become engaged with the clutchteeth 222 to step up the drive in the transmission to overall fourthspeed or high speed drive which is a direct two-way drive. In this drivethe planetary continues to function in its high range i.e., 1:1 ratiounder drive by the engine and eddy current clutch and the drive in thecountershaft unit is direct through shaft 136, clutch teeth 222, sleeveJ, gear 184, clutch teeth 196, sleeve 192, hub 190, driven shaft 12.This drive provides an overall 3:1 drive ratio for cruising.

It will be observed that although the switch O is operated during theabove upshift operation no ignition interruption will occur since theignition interruption circuit is also controlled by the governor Mswitch 340 which isfthen open. l

When driving in fourth speed and rapid acceleration is desired as, forexample, when passing cars at speeds above the operating speed ofgovernor M or when climbing hills, two-way third speed or highintermediate drive providing an overall ratio of 4.2 and a transmissionratio .of .1.4 may be obtained by kickdown operation of the acceleratorpedal 224. Depression of the pedal 224 to or beyond wide open throttleposition (whichever has been provided for) actuates the link 376 andlever 380 Vand causes the nger 388 of the latter to engage the op-;erating lever 370 of the snap switch 364, actuation of which opens thecircuit between conductors 371 and 363 to deenergize the eddy currentclutch'coil 62. Substantially simultaneously the circuit is closedbetweenthe 4conductors 373 and 363 to energize the eddy current brakecoil 78. This operation will produce the flux eect previously describedon the teeth 107 of the drum of the eddy current driven member 24 andwill slow down the rotation of this member whether forward or reverseand cause it to stop whereupon the direct magnetic pull of the ux willhold it stationary. Since the sun gear 110 is positively connected tothe eddy current member 24 it also will be held stationary and theplanetary gearset F will, through reaction on the sun gear 110 transmita torque multiplying drive to shaft 136 whereupon the vehicle will beaccelerated in underdrve at a speed dependent upon the speed of theengine A, the countershaft gearing G being then in direct drive. It willbe understood that torque will be imposed on the shaft 136 from theinstant the eddy current member 24 begins to slow down.

Acceleration of the vehicle in third speed (thigh intermediate) may becontinued as long as desired, the operator having a substantial range ofcontrol over the throttle without operating the switch 364 and whensuicient vehicle speed has been attained the coil 73 may be deenergizedby releasing movement of the accelerator pedal suflicient to operate theswitch 364 to open the coil 78 circuit and re-establish coil 62 circuitwhereupon the driven member 24 will again be magnetically coupled withthe driving member 22 for forward rotation therewith in fourth speed.

It will be understood that a similar kickdown operation to attaingreater acceleration may be employed when the Vehicle is being driven inoverall second speed ratio drive described above at which time theplanetary is operated by the eddy current clutch in direct drive ratioand the countershaft gearing is established in low speed, i. e. indirectdrive. Under such circumstances the planetaryV gearing F will as abovedescribed be downshifted to its low speed or underdrve ratio (the sungear being held) and since the countershaft gearing G is then also beingdriven through its low speed (indirect drive) train (the Sleeve J beingdisengaged) overall first speed or conventional, low speed ratio drivewill be obtained from this combination of underdrve in thel planetaryand .underdrve in the countershaft mechanism. This asegure 15 provides a3.5:1 transmission ratio and `overall 10.5.21 ratio.

When the vehicle is permitted to slow down as 'when coming to a stopwhile operating in third or fourth speed ratio drive, the governor Mswitch 340 will close when the vehicle reaches a speed somewhat below l5miles per hour, for instance, about lO 'miles per hour, thus energizingthe solenoid L and causing the core member 282 to move upwardly and openthe valve 28'4 to vent the motor K. This will allow the spring 270 toactuate the rod 256 against the abutment 254, vthe latter operating thelever 25o and yoke 234 to disengage the clutch sleeve J. To facilitatedisengagement the rod 256 in taking up the gap 278 between it and theabutment 254 (see Figure 9) has its recess 328 actuate the ball 316 ofthe switch O closing the switch and thus connecting the ignition toground 346 through the governor switch 340A which is then closed tothereby interrupt the ignition and release the driving torque on theteeth of the clutch sleeve. The ground is removed from the. ignitioncircuit and normal operation again restored when the portion 326 of therod 256' is moved below the ball 316 allowing it to drop and permittingthe spring 324 to open the switch O.

If the vehicle was being operated in overall fourth speed, it now willfunction in overall Second speed. On the other hand, if it was operatingin (kickdown) overall third speed the car will be accelerated in overallfirst speed. When the car is brought to a standstill and the acceleratoris released suiciently to obtain engine idling condition, the` governorN will open the circuit bet-Ween conductors 357 and 363 by disengagingthe, operating lever 358 from the contact 36,1. This will deenergizeVthe eddy current coil circuit until then energized and preventtransmission of torque. Thisv feature makes it possible to bring the carto a stop at a traffic light and with the transmission in gear andwithout obtaining creep. When the light changes, the operator simplydepresses the accelerator to speed up the engine to the speed at whichit will cause the governor N to close the coil circuit previously openedand permit transmission of driving torque.

It will be understood that reverse drive will be obtained by shiftingthe sleeve 192 rearwardly in Figure 5 to engage with the clutch teeth198. Upon depression of the accelerator drive will be initiated inreverse through the eddy current clutch B and drive shaft 20 theseoperating thel planetary F in 1:1 or high ratio and the spider of theplanetary impressing drive torque on the shaft 136 which then drives theshaft 12 through the elements 171, 172, freewheeling clutch H 182, 188,186, 198, sleeve 192, hub 190. This will provide a 3:1r ratio in thetransmission and an overall ratio of 9:1.

Manifestly, faster speed ratio drives in reverse are also available.Thus the sleeve J will be brought into engagement with the clutch teeth4222 asA above described under control of the governor M which beingdriven from the countershaft will operate at a proportionately lowervehicle speed than when effecting a step-up in forward drive. Greateracceleration in reverse is also available by kickdown operation of theaccelerator pedal to deenergize the eddy current clutch and energize theeddy current brake and obtain, a step-down in the planetary gearing F tolow speed ratio, in this case fromf direct drive to underdrive. This maybe accomplished atv the will of the driver whether or not the reversedrive be one in which the sleeve J is engaged or disengaged.

Figure l illustrates' a modification of the construc-y tion of Figurewherein theV magnetic path of theeddy current clutch structure ismade'shorter by magnetically connecting the field core with both toothedelements of the drive member of the clutch. This' arrangement alsopermits a substantial saving in iron.

TChus.Y in Figure l0`` the: field structurer is4 an" annularChannel-shaped. eld' core; member 60A ofVv magnetici iron on' other.magnetic material., stationarily secured to the ycasing 52A, which hereis of non-magnetic material, and carries the stationaryv field coil 62A.Rotatable relative to the -field core is the drive member 22A, the innerltoothed element 26A of which has its hub portion 32A arrangedconcentric to the ange 400 of the field core, and the outer toothedelement 36A of which is arranged concentric to the flange 482 of thefield core and in radial alignment with the flange 400 and hub 32A.Operating clearance is provided by air gaps of about .005 of an inchbetween the toothed elements of the drive member 22A and the augeportions of the field core. An annular spider 42A connects Athe elements26A and 36A. The starter ring gear 50 is here carried by the toothedelement 36A.

The eddy current brake structure is similar to that in Figure 5 exceptthat the casing portion 53A has an upward flange 404 bolted to a casingportion 52A of nonmagnetic material.. The operation of this modificationis similar to that described with respect to the Figure 5 structure. p

Figure 11 shows a modification of the Figure 9 control circuits, itdiffering from the Figure 9 arrangement in that the ignitioninterrupting circuit operated under control of the switch O to unloadthe teeth of the clutch sleeve I and permit disengagement of this sleeveis replaced with a new circuit acting on the eddy current mechanism toeffect a similar result. Since the major portion of the Figure llarrangement is the same as that in Figure 9. only the alteredportion hasbeen shown completely, the remainder being obvious from Figure 9 aswill, be evident from the numerals of conductors duplicated in Figure11.

Thus the conductor 336 extends from the ignition switch` 329 to a fourpole switch generally referred to by the numeral 3411A which is operatedby a link arm 306 connected to the vehicle speed responsive governor M.The arm 306 carries two switch closing conductor bars 486 and 488respectively, which serve to bridge the terminals 410, 412 and 414, 416respectiveiy when the switch is closed.` The Conductor 336 aforesaidconnectsl with the terminal 410 and the terminal 412 is connected by aconductor 418 withone end of the solenoid L coil, the other end of thecoil being grounded as at 420. As shown the coil. L is energized andAtheA sleeve I is in downshifted position.

The energizing circuit for the eddy current clutch coil 62 in the Figurel1 arrangement extends through the interruptor s'witch O' which as seenis a. double pole double throw switch. This switch has a pair ofterminals 422: and. 424` bridged by a` conductor 426' and electricallyconnecting such terminals whenever th: motor K has completed itsYupshift or downshift operation onl the sleeve J through. movement ofthe. rod 256. The switch4 O has a further" pair of.' terminals 428, 430which are bridged by the conductor 426 whenever the ball 316l isactuatedby the rod 256 in movement of the latter to engageVV the ball. 316.` ineither th'eportion 326 or recess 328 from the other;V

Thus,` the energizing, circuitfor coil 62Y comprises' the circuit frombattery 144 to ignition switch 329, conductor 336, conductor 347',switch1349 and 359 (see Figure 9), conductor. 363,. tereminal 366,conductor 369, terminal 365, conductor 432, terminal 424', conductor-426, terminal 422;. conductor 434;` coil- 62, ground 372;

ltr obtaining? downshift ofthe clutch sleeveI I under control ofgovernorA M1 by closing of switch 340A the rod 256 moves from'` a1position where the' ball isf engaged'l in recess 328' t'othat; showniniFigure lllwhere it engages' portion 326. in`v the`- travel between'these positions the: ball 316 actuates the conductor 426 to breakV thecircuit across terminals. 422', 4241 and7 bridge the terminals; 428,43l`thus momentarily breaking the circuitdesc'ribedlab'oved'eenergizinge this coil and'V energizing the eddycurrent rakecoil 78..,y AWhen this occurst currentf will ow fronr 1batteryil'ifitof savitcha 3291,16 switches349i and: 3591 (see Figure 9)conductor 363, conductor 436 to terminal 416 of switch 340A, conductor408, terminal 414, conductor 438, terminal 430, conductor bar 426,terminal 428, conductor 440, terminal 368, conductor 373 to coil 78 andground 374. Of course. as soon as the ball 316 is established in one ofthe positions 326 or 328 the coil 62 circuit will be reestablished. Theeffect of this momentary deenergizing of coil 62 and energizing coil 78is to momentarily remove the driving load on the teeth of the clutchsleeve J the sleeve tending to overrun the clutch teeth 222 to permitthis result. It will be noted that although the switch O is alsooperated in making upshifts by clutch sleeve J no change of power flowwill occur since the governor switch M is then open and the eddy currentclutch coil 62 remains energized by reason of the closing of a switch440 by governor M when it opens the switch 340A. The switch 440 hasterminals 442, 444 which are bridged to electrically connect them incircuit by the conductor bar 446. Thus in making upshifts the coil 62remains energized during operation of switch O' through a circuitextending from terminal 365 of kickdown switch 364, to conductor 432 toconductor 446 to terminal 444, conductor bar 446, terminal 442,conductor 448, conductor 434 to coil 62.

Figure 12 shows a modication of the kickdown control portion of theFigure 9 and 11 control circuits. It provides a double pole double throwswitch 450 operated under control of a speed responsive centrifugalgovernor P driven by the countershaft gear 304 for limiting kickdownoperation of the eddy current mechanism to at or below a predeterminedvehicle speed for instance, 40 m.p.h.

The switch 450 has terminals 452 and 454 `bridged by a conductor bar 456when the Vehicle is below 40 m.p.h. speed. The terminal 452 connectswith the eddy current brake coil 78 through the conductor 373 and theterminal 454 with terminal 368 of the kickdown switch 364 through theconductor 457. So long as the terminals 454 and 456 are bridged,operation of the kickdown switch 364 by the accelerator pedal 224 willconnect the terminal 368 to battery through the conductor 363 as in theFigure 9 arrangement. However, above 40 m.p.h. vehicle speed theconductor bar 456 will bridge the terminals 458 and 460, the formerbeing connected to the kickdown switch terminal 368 by the conductor 457and the latter connecting with the terminal 365 of the kickdown switchto which the coil 62 is connected by the conductor 371. Thus if thekickdown switch be operated above 40 m.p.h. vehicle speed the eddycurrent brake coil 78 Will not be energized because the terminals 454and 456 of switch 450 are no longer bridged. Instead the eddy currentclutch coil remains energized through the circuit established bybridging of the terminals 458 and 460.

This control circuit has a further function and advantage. If adownshift is obtained by kickdown operation below 40 mph. and theaccelerator is not thereafter released sufiiciently to reset thekickdown switch so as to restore drive through the eddy current clutch,but the vehicle attains a speed above 40 m.p.h so as to cause thegovernor switch 45t) to operate, a power upshift will take placeautomatically independently of accelerator pedal position since theplanetary F is upshifted from underdrive to direct by the change back tothe eddy current clutch drive from the eddy current brake drive.

Moreover, if a downshir't is obtained by kickdown operation of theFigure 9 circuit or below 40 m.p.h. by the Figure l2 circuit while thevehicle is operating in fourth speed so as to establish third speedforward and the vehicle is maintained in third speed by exercise of thehereinabove mentioned control provided by the throttle a seconddownshift will automatically occur as soon as the governor M switchcloses at about m.p.h. vehicle speed to establish first speed. Releaseof the accelerator to operate the kickdown switch will automaticallyreestablish second speed instead of third speed.

Although the particular structures herein described are well adapted forcarrying out the objects of the invention it will be understood thatvarious modifications, changes, and substitutions may be made withoutdeparting from the spirit thereof. For example, where flux leakagebecomes too great a problem in an arrangement employing an eddy currentclutch and brake the brake may, as illustrated in Figure 13, be replacedfor instance, by a multiple disc magnetic clutch E serving as a brakefor holding the sun gear from rotation and which includes an annularcore 76 stationarily secured as by bolts 77 to the casing element 53 anda field coil assembly 78 adapted to be energized and deenergized in themanner described with respect to the eddy current brake coil 78. Anon-magnetic sleeve 500 is xed to the core 76 and has internal splines502 which slidably fit in slots 504 of the movable friction discs 506and which interengage with a movable magnetizable armature 508. Otherfriction discs 510 alternate axially with the discs 506 and are slidablysplined as at 511 on a projecting annular portion 512 of the drivenmember 24 structure, of which the sun gear 110 forms a part. A snap ring514 holds the armature 508 endwise on the sleeve 500. In operation ofthe device as when the coil 78 is energized in the manner describedabove with respect to the coil 78, the armature 568 is drawn toward thepole faces of the core 76 and effects pressure contact between thejuxtaposed `friction discs thereby clutching the driven member to thecore 76' and serving to hold the driven member 24 from rotation.

It will be further understood that the various features disclosed anddescribed may be combined in `ways other than those shown withoutdeparting from the present invention. For example, the governors M and Pcould be combined. The present invention is therefore, to be construedto include all such modifications, changes and substitutions as may comewithin the scope of the following claims.

I claim:

1. In an electromagnetic clutch, a rotatable driving member having twomagnetically separate magnetic portions, each of said magnet-ic portionshaving radial polar projections which are spaced from the polarprojections of the other magnetic portion, a rotatable driven memberhaving a cylindrical magnetic portion constituted by a substantiallyuninterrupted magnetic surface intermediate the polar projections ofsaid two magnetically separate portions, all of said polar projectionsand cylindrical portion lying substantially in the same plane and thepolar projections of one of said separate magnetic portions being inangular alignment with the polar projections of the other portion, andstationary field means for completing a magnetic flux path across saidpolar projections.

2. In an electromagnetic clutch as claimed in claim l wherein said polarprojections have side portions converging to the tips of saidprojections whereby to produce magnetic saturation at said tips.

3. In an electromagnetic clutch; a rotatable driving member having outerand inner magnetically separate, magnetic elements of cylindrical shape,said outer element having internal radial teeth tapering from adjacenttheir base portions to their tips, said inner element having externalradial teeth spaced from the internal teeth of the outer element and inangular alignment therewith, said inner element teeth having asubstantially uniform cross-section for the greater portion of theirradial length and tapering toward their tips from a point adjacentthereto; a rotatable driven member having a continuous cylindrical wallof substantial equal section throughout its periphery, arranged torotate intermediate and in close proximity to the radial teeth of saidouter and inner elements; all of said teeth and wall lying-substantiallyin the same plane and there being stationary field means for completinga magnetic ux path across said angularly aligned teeth.

4. In an electromagnetic clutch, a rotatable driving member having twomagnetically separate but structurally connected magnetic portions, eachof said magnetic portions having radial polar projections which arespaced from the polar projections of the other magnetic portion; arotatable driven member having a cylindrical magnetic portionconstituted by a substantially uninterrupted magnetic surfaceintermediate the polar projections of said two separate magneticportions, all of said polar projections and said uninterrupted surfacelying substantially in the same plane and the polar projections of oneof said separate magnetic portions being in anguiar alignment with thepolar projections of the other portion; one of said magnetic portionshaving an axially extending hub; a stationary magnetic core piecesurrounding said hub and supporting a magnetic casing portionsurrounding the other of said magnetic portions; and a stationary fieldcoil carried by said core piece.

5. In an electromagnetic clutch and brake structure, a rotatable clutchmember having two magnetically separate magnetic portions, a stationarybralte member having two magnetically separate magnetic portions; saidmagnetic portions of said clutch and brake members re spectively havingtwo concentric radially spaced sets of radial polar projections; andsaid structure including a rotatable hollow drum having iirst and secondmagnetic portions respectively positioned intermediate the sets of polarprojections respectively of the clutch and brake members, the said firstportion constituting a continuous ring constituted by a substantiallyuninterrupted magnetic surface and said second portion constituting aring-like arrangement of axially extending polar projections.

6. An electromagnetic clutch and brake structure as claimed in claimwherein the axially extending pola.: projections of the drum are ofrectangular shape.

7. In an electromagnetic clutch and brake structure, a rotatable clutchmember having two magnetically separate magnetic portions; a stationarybrake member having two magnetically separate magnetic portions; each ofsaid magnetic portions of said clutch and brake members having radialpolar projections which are spaced from the polar projection of theother of said two magnetic portions respectively of said clutch andbrake members; a rotatable driven member having an annular rim portionand an intermediate supporting web, one end of said rim being arrangedintermediate the polar projections of said two magnetically separateportions of the clutch mem* ber and constituting a substantiallyuninterrupted magnetic surface portion and the other end of said rimbeing arranged intermediate the polar projections of said twomagnetically separate portions of the brake member and being providedwith axially extending polar projections; the polar projections of saidclutch member and said unipolar portion of said driven member being insubstantially the same plane and the polar projections of said brakemember and the axially extending polar projections of said driven memberalso being in substantially the same plane.

8. In an electromagnetic clutch and brake structure, a rotatable clutchmember having two magnetically separate magnetic portions, a stationarybrake member having two magnetically separate magnetic portions; saidmagnetic portions of said clutch and brake members respectively havingconcentric radially spaced sets of radial polar projections; a rotatablehollow drum having first and second magnetic portions respectivelypositioned intermediate the sets of polar projections respectively ofthe clutch and brake members, the said first portion constituting acontinuous ring constituted by a substantially uninterrupted magneticsurface and said second portion constituting a ringwlilre arrangement ofaxially extending polar projections, and a casing surrounding saidclutch and brake structure, said casing having an annular portionthereof forming part of the magnetic circuit of the clutch structure andanother annular portion forming part of the magnetic circuit of thebrake structure.

9. in an electromagnetic clutch and brake structure, a rotatable clutchmember having two magnetically separate magnetic portions; a stationarybrake member `having two magnetically separate magnetic portions; saidmagnetic portions of said clutch and brake members respectively havingconcentric radially spaced sets of radial polar projections; a rotatablehollow drum having first and second magnetic portions respectivelypositioned intermediate the sets of polar projections respectively ofthe clutch and brake members, the said first portion constituting acontinuous ring constituted by a substantially uninterrupted magneticsurface and said second portion constituting a ring-like arrangement ofaxially extending polar projections, a casing surrounding said clutchand brake structure, said casing having an annular portion thereofforming part of the magnetic circuit of the clutch structure and anotherannular portion forming part of the magnetic circuit of the brakestructure and there being a non-magnetic spacer separating said casingportions.

10.1n an electromagnetic clutch and brake structure, a rotatable clutchmember having two magnetically separate magnetic portions; a stationarybrake member having two magnetically separate magnetic portions; saidmagnetic portions of said clutch and brake members respectively havingconcentric radially spaced sets of radial polar projections; alrotatable hollow drum having rst and second portions respectivelypositioned intermediate the sets of polar projections respectively ofthe`clutch and brake members, the said first portion constituting acontinuous ring constituted by a substantially uninterrupted magneticsurface and said second portion constituting a ring-like arrangement ofaxially extending polar projections.

ll. In an eddy current clutch and brake structure, a rotatable outputmember comprising a hollow drum having a portion ofl its length adjacentone end thereof formed with a continuous cylindrical wall ofsubstantially equal thickness throughout and having a portion of itslength adjacent its opposite end formed with a continuous ring ofaxially extending teeth constituting polar projections of a magneticcircuit and further having a supporting web intermediate said portions.

References Cited in the le of this patent UNITED STATES PATENTS 643,413Kennedy Feb. 13, 1900 1,271,401 Weydell July 2, 1918 v1,277,371 BoyleSept. 3, 1918 1,702,755 Weydell Feb. 19, 1929 2,170,460 Murray Aug. 22,1939 2,277,284 Winther Mar. 24, 1942 2,286,777 Winther June 16, 19422,333,863 Hull Nov 9, 1943 2,334,976 Winther Nov. 23, 1943 2,409,557Gilllan Oct 15, 1946 2,444,797 Williams July 6, 1948 2,470,249 KarasickMay 17, 1949 2,488,827 Pensabene Nov. 22, 1949 2,492,776 Winther Dec.27, 1949 FOREIGN PATENTS 981,986 France lan. 24, 1951

